Surfboard Stringer Reinforcing system

ABSTRACT

A reinforcing system for a floatation device, such as a surfboard, and a method of its manufacture is disclosed. Such a floatation device has an elongated stringer that has at least a top edge and a bottom edge. The reinforcing system of the present invention includes an elongated top bracket and an bottom bracket. The top and bottom sides of each bracket are wider than the top and bottom edges of the stringer. The cross-sectional shape of the top bracket is preferably rectangular, forming an I-beam cross-section when each bracket is fixed to the stringer with a fastening means, such as a strong adhesive or screws. The floatation device is preferably of the type having two buoyant blanks, each adhered to one side of the stringer. During fabrication of the floatation device, each blank is fixed at one substantially flat side thereof to one side of the stringer with adhesive. A pair of notches may then be cut into each blank and the stringer to accommodate each bracket, which is then fastened with the fastening means to each blank and to the stringer, resulting in each blank being adhered to the stringer and each bracket. Alternately, or additionally, each bracket may be fastened to the stringer with a plurality of the screws. The assembled floatation device may then be sanded and then coated with a resin coating, applied over each blank, the stringer and each bracket.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

Not Applicable.

FIELD OF THE INVENTION

This invention relates generally to floatation devices, and more particularly to a stringer reinforcing system for a surfboard.

DISCUSSION OF RELATED ART

Typical surfboard blanks are either made from a pressure-molded polyurethane or polystyrene material, either as a single piece or with a pair of buoyant foam blanks fixed to each side of a rectangular cross-section reinforcing stringer. If included, the stringer is typically made of balsa wood, a strip of adhesive, or other light-weight materials, and provides some amount of strength to the surfboard against breaking when strongly impacted by waves, the seabed, or other object. Even so, such conventional surfboards are still routinely subject to breaking laterally across the board and stringer. Surfboards are rarely broken longitudinally, clearly indicating a need for improving the lateral strength of such boards.

Several prior art devices have been developed to strengthen surfboards and like recreational devices. For example, U.S. Pat. No. 4,767,369 to Snyder on Aug. 30, 1988, teaches an improved water ski having in addition to a conventional stringer a pair of traversely spaced longitudinal core members. Such additional reinforcing core members, while aiding in the strength of such a ski, do not provide additional strength against breaks that originate in the bottom surface of the ski, such as may happen if a strong impact is experienced at the top central portion of the ski, forcing the ends of the ski upward and the center of the ski downward. As surfboards are typically thicker than skis, such a reinforcing design is even less suited for surfboards, particularly with large waves impacting any portion of the board. Such impacts frequently are strong enough to laterally break surfboards, the breaking point starting on the rear surface thereof. Such impacts would also be strong enough to break surfboards with such reinforcing members only in the top portion of the board, as such reinforcing core members are necessarily flexible somewhat along their length and would provide little resistance to such flexing and breaking of the surfboard.

U.S. Pat. No. 5,921,833 to Bixby on Jul. 13, 1999 teaches a stringer having a center panel with a pair of longitudinal cavities formed therein for hollow shaft members. The center panel of such a device is bordered by two conventional stringers. Such a device, while effective, is unnecessarily complex and expensive to manufacture. Such a device further changes the nose and tail shapes of the board and, as such, must be offered in a variety of suitable shapes. Further, such a device does nothing to provide additional support beyond the stringers to the foam blanks, which are the weakest portions of the board and where board failures typically being when the board is strongly impacted.

U.S. Pat. No. 4,798,549 to Hirsch on Jan. 17, 1989, teaches a hollow stringer having additional branches [Col. 2, Line 25] for intermingling with injected foam on either side of the stringer. Such a stringer, however, and the required method of manufacturing a surfboard with such a stringer, is unnecessarily complex and requires additional tooling and manufacturing space to accommodate such tooling. Surfboard manufacturers need to have a means of strengthening surfboards without requiring a complete overhaul of their manufacturing facilities. Further, the stringer of such a device is unusually thick and cannot be made of various woods and adhesives. Such a stringer, moreover, cannot be added to a conventionally made surfboard.

Therefore, there is a need for an improved stringer reinforcing system that may be optionally added to any surfboard or like device that is made with conventional fabrication methods and tooling. Such a needed system would provide an I-Beam stringer shape, greatly increasing the lateral breaking resistance of any surfboard into which it is installed. Further, such a needed system would not greatly increase the cost or complexity of manufacturing such a board, and the finished surfboard would still be aesthetically pleasing. Such a needed invention could be used with any conventional solid blank or stringer and foam blanks combination. The present invention accomplishes these objectives.

SUMMARY OF THE INVENTION

The present device is a reinforcing system for a floatation device, such as a surfboard. Such a floatation device has an elongated stringer that has at least a top edge and a bottom edge. The reinforcing system of the present invention includes an elongated top bracket comprising a top side, a bottom side, and a peripheral side edge. The top and bottom sides are each wider than the top and bottom edges of the stringer. The cross-sectional shape of the top bracket is preferably rectangular. A similar elongated bottom bracket is also included. Such brackets may be made from a carbon fiber-based material, a plastic material, a resin material, or the like, provided that the bracket has suitable strength against breaking yet is somewhat resilient so as to accommodate a small amount of flexing during use.

A fastening means is included for fastening the top bracket to the top edge of the stringer and for fastening the bottom bracket to the bottom edge of the stringer. Such a fastening means may be screws, or other suitable fastening means as is known in the art.

The floatation device is preferably of the type having two buoyant blanks, each adhered to one side of the stringer. Such buoyant blanks are typically made of a foam or other buoyant material that is easily formed and cut. Each blank has at least one substantially flat side for fixing to one side of the stringer.

Typically, during fabrication of the floatation device, each blank is fixed at the one substantially flat side thereof to the one side of the stringer with adhesive or other bonding means. A pair of notches may then be cut into each blank and the stringer to accommodate each bracket, which is then fastened with the fastening means to each blank and to the stringer, resulting in each blank being adhered to the stringer and each bracket. Alternately, or additionally, each bracket may be fastened to the stringer with a plurality of the screws. Such brackets fastened to the stringer result in the reinforcement system having a relatively strong I-beam construction. The assembled floatation device may then be coated with conventional fiberglass cloth and resin coating, applied over each blank, the stringer and each bracket.

The present invention is an improved stringer reinforcing system that may be optionally added to any surfboard or like device that is made with conventional fabrication methods and tooling. The present invention results in an I-Beam stringer shape, greatly increasing the lateral breaking resistance of any floatation device into which it is installed. Further, use of the present system does not greatly increase the cost, complexity or time of manufacturing such a board, and the finished surfboard is still aesthetically pleasing and not much different in appearance than surfboards without such a device. As such, the present invention may be used with any conventional stringer or foam blanks. Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of the invention, illustrating a reinforcing system for a floatation device;

FIG. 2A is a partial cross-sectional view of the invention, taken generally along lines 2-2 of FIG. 1;

FIG. 2A is a partial cross-sectional view of the invention, taken generally along lines 2-2 of FIG. 1, and illustrating an alternate embodiment of the invention;

FIG. 3 is a partial exploded view of the invention;

FIG. 4 is a cross-sectional view of an alternate embodiment of the invention, taken generally along lines 2-2 of FIG. 1; and

FIG. 5 is a partial exploded view of the alternate embodiment of the invention;

FIG. 6 is a cross-sectional view of another alternate embodiment of the invention, taken generally along lines 2-2 of FIG. 1;

FIG. 7 is a cross-sectional view of yet another alternate embodiment of the invention, taken generally along lines 2-2 of FIG. 1;

FIG. 8 is a cross-sectional view of a top or a bottom bracket of the invention made from a corrugated plastic material; and

FIG. 9 is a top plan view of the floatation device, illustrating an alternate embodiment of the top bracket that includes a traction pad.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 illustrates a reinforcing system 10 for a floatation device 20, such as a surfboard. Such a floatation device 20 has an elongated stringer 30 that has at least a top edge 34 and a bottom edge 36. Such stringers 30 are typically made from balsa wood, carbon fiber-based material, epoxy resin, plastic, or the like.

The reinforcing system 10 of the present invention includes an elongated top bracket 40 comprising a top side 41, a bottom side 42, and a peripheral side edge 43. The top and bottom sides, 41, 42 are each wider than the top and bottom edges 34, 36 of the stringer 30. The cross-sectional shape of the top bracket 40 is preferably rectangular, as illustrated best in FIG. 2A. Such a top bracket 40 may be made from a carbon fiber-based material, a plastic material, a resin material, or the like, provided that the bracket 40 has suitable strength against breaking yet is somewhat resilient.

Similarly, an elongated bottom bracket 50 is also included that comprises a top side 51, a bottom side 52, and a peripheral side edge 53. The top and bottom sides, 51, 52 are each wider than the top and bottom edges 34, 36 of the stringer 30. The cross-sectional shape of the bottom bracket 50 is also preferably rectangular (FIG. 2A). Such a bottom bracket 50 may be made from a carbon fiber-based material, a plastic material, a resin material, or the like, provided that the bracket 50 has suitable strength against breaking yet is somewhat resilient so as to accommodate a small amount of flexing during use. Each bracket 40, 50 may be wider, proportionally, than shown in FIGS. 2A, 2B, and FIG. 3, as desired.

A fastening means 60 is included for fastening the top bracket 40 to the top edge 34 of the stringer 30 and for fastening the bottom bracket 50 to the bottom edge 36 of the stringer 36, as illustrated in more detail in FIGS. 3 and 4. Such a fastening means 60 may be screws 90 (FIGS. 4 and 5), adhesive 80 (FIGS. 2A and 3), rivets (not shown), or other suitable fastening means as is known in the art. In the case where the fastening means 60 is screws 90, the top and bottom brackets 40, 50 may include apertures 95 therethrough (FIG. 5) so that the screws 90 may be mounted flush with the top side 41 and bottom side 52 of each bracket 40, 50, respectively.

The floatation device 20 is preferably of the type having two buoyant blanks 70, each adhered to one side 38 of the stringer 38. Such buoyant blanks 70 are typically made of a foam or other buoyant material that is easily formed and cut. Each blank 70 has at least one substantially flat side 75 for fixing to one side 38 of the stringer 30.

Typically, during fabrication of the floatation device 20, each blank 70 is fixed at the one substantially flat side 75 thereof to the one side 38 of the stringer 30 with adhesive 80 or other bonding means as is known in the art. Optionally, a pair of notches 77 may then be mortised or routed into each blank 70 and the stringer 30, if present, to accommodate each bracket 40, 50 (FIG. 2A). A standard 3″ shaping planer (not shown), for example, may be used to cut such notches 77 in the floatation device 20. Alternately, as illustrated in FIG. 2B, the notches 77 may be omitted. Each bracket 40, 50 is then fastened with the fastening means 60 to each blank 70 and to the stringer 30 (FIG. 2A), resulting in each blank 70 being adhered to the stringer 30, the peripheral edge 43 and the bottom side 42 of the top bracket 40, and to the peripheral edge 53 and the top side 51 of the top bracket 50. Clearly the notches 77 may be cut into each blank 70 and the stringer 30 before adhering the blanks 70 to the stringer 30. Alternately, or additionally, each bracket 40, 50 may be fastened to the stringer 30 with a plurality of the screws 90 (FIGS. 1, 4 and 5). Such brackets 40, 50 fastened to the stringer 30 result in the reinforcement system 10 having a relatively strong I-beam construction, as illustrated best in FIG. 2A.

Such an assembled floatation device 20 may then be covered with a conventional fiberglass cloth and coated with a resin coating 100, applied over each blank 70, the stringer 30 and each bracket 40, 50. Clearly, either the top bracket 40 or the bottom bracket 50 may be included alone, without the other bracket 50, 40, respectively, and still reinforce the strength of the stringer 30.

In one embodiment of the invention, illustrated in FIGS. 4 and 5, each bracket 40, 50 further includes two projecting side portions 48, 58, resulting in a U-shaped channel 46, 56 being defined thereby. Such a U-shaped channel 46, 56 receives one edge 34, 36 of the stringer 30 therein for further reinforcing the strength of the stringer 30, and hence the floatation device 20. The brackets 40, 50 may be made from a bent or otherwise formed sheet material, having a gauge or thickness as deemed appropriate for each application or floatation device 20 owner. The gauge shown in FIGS. 4, 5 is not drawn to scale, but could be thicker or thinner as necessary.

FIGS. 6 and 7 illustrate other alternate embodiments of the invention, wherein the brackets 40, 50 are adhered over the resin coating 100 on a top surface 104 and a bottom surface 106 of the floatation device 20, preferably substantially covering the stringer 30 if included in the floatation device 20. Such embodiments provide for either a rounded top side 47 (FIG. 6) or tapered top side 49 (FIG. 7) of the top bracket 40, and a rounded bottom side 57 (FIG. 6) or a tapered bottom side 52 (FIG. 7) of the bottom bracket 50, thereby providing a smoother transition between the brackets 40, 50 and the resin coating 100. The fastening means 60 may be a strip of the adhesive 80 with a protective liner strip (not shown) that is removed just before applying the brackets 40, 50 to the floatation device 20. The adhesive 80 in such embodiments is a suitably strong, water-resistant adhesive that adheres each bracket 40, 50 to the resin coating 100 permanently. Alternately, the top and bottom brackets 40, 50 may be each made from a corrugated plastic material 110, such as Lexan or the like (FIG. 8).

In one embodiment of the invention, illustrated in FIG. 9, the top bracket 40 includes a traction pad 45 at a rear end 44 thereof. Such a traction pad 45 provides a high-traction surface (not shown) for increasing the traction between the user and the floatation device 20. The traction pad 45 may be integrally formed with the top bracket 40, such as by a plastic sheet stamping process or the like.

While a particular form of the invention has been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the invention. For example, the exact placement of each bracket 40, 50 with respect to the entire floatation device 20 may be modified, as may the length of each bracket 40, 50. Further, the exact type of attachment means 60 may be any suitable type of adhesive, any suitable type of mechanical fastener, or the like as becomes known in the art. Accordingly, it is not intended that the invention be limited, except as by the appended claims. 

1. A reinforcing system for a floatation device having a resin coating applied on an outer surface thereof and at least a top surface and a bottom surface, the reinforcing system comprising: an elongated top bracket comprising a top side, a bottom side, and a peripheral side edge; an elongated bottom bracket comprising a top side, a bottom side, and a peripheral side edge; and a fastening means for fastening both the top bracket to the resin coating of the top surface of the floatation device, and the bottom bracket to the resin coating of the bottom surface of the floatation device; whereby the brackets reinforce the floatation device at both the top and bottom surface.
 2. The reinforcing system of claim 1 wherein the floatation device includes a longitudinal stringer fixed between two buoyant blanks, the resin coating applied thereover, and wherein the top bracket is fastened to the resin coating of the top surface substantially covering the stringer, and the bottom bracket is fastened to the bottom surface substantially covering the stringer.
 3. The reinforcing system of claim 1 wherein the top side of the top bracket and the bottom side of the bottom bracket each have a rounded surface.
 4. The reinforcing system of claim 1 wherein the top side of the top bracket and the bottom side of the bottom bracket each have a tapered surface.
 5. A reinforcing system for a floatation device that has an elongated stringer having at least a top edge and a bottom edge, the reinforcing system comprising: an elongated top bracket comprising a top side, a bottom side, and a peripheral side edge, the top and bottom sides being wider than the top and bottom edges of the stringer; an elongated bottom bracket comprising a top side, a bottom side, and a peripheral side edge, the top and bottom sides being wider than the top and bottom edges of the stringer; and a fastening means for fastening the top bracket to the top edge of the stringer, and the bottom bracket to the bottom edge of the stringer; whereby the brackets reinforce the stringer of the floatation device upon assembly of the brackets and stringer into the floatation device.
 6. The reinforcing system of claim 5 wherein the floatation device is of the type having two buoyant blanks, each adhered to one side of the stringer, and wherein each blank and the stringer is further cut to accommodate each bracket.
 7. The reinforcing system of claim 6 wherein each blank is adhered to one side of the stringer and to the peripheral edge and one side of each bracket.
 8. A floatation device comprising: an elongated rectangular stringer defined by a top edge, a bottom edge, and two sides, each side being substantially parallel to the other; a pair of buoyant blanks, each having one substantially flat side for fixing to one side of the stringer; an elongated top bracket comprising a top side, a bottom side, and a peripheral side edge, the top and bottom sides being wider than the top and bottom edges of the stringer; an elongated bottom bracket comprising a top side, a bottom side, and a peripheral side edge, the top and bottom sides being wider than the top and bottom edges of the stringer; and a fastening means for fastening the top bracket to the top edge of the stringer and the bottom bracket to the bottom edge of the stringer.
 9. The floatation device of claim 8 wherein a pair of notches are cut into each blank and the stringer to accommodate each bracket.
 10. The floatation device of claim 8 wherein each blank is fixed to the stringer and to one side and the peripheral edge of each bracket with adhesive.
 11. The floatation device of claim 8 wherein the fastening means is a plurality of screws.
 12. The floatation device of claim 9 wherein the fastening means is adhesive.
 13. The floatation device of claim 9 wherein the fastening means is a resin coating applied over the blanks, stringer, and brackets.
 14. The reinforcing system of claim 1 wherein each bracket further includes two projecting side portions, a U-shaped channel defined therebetween for receiving one edge of the stringer therein.
 15. The floatation device of claim 8 wherein each bracket further includes two projecting side portions, a U-shaped channel being defined therebetween for receiving one edge of the stringer therein.
 16. The floatation device of claim 1 wherein the top bracket further includes at a rear end thereof a traction pad.
 17. The floatation device of claim 5 wherein the top bracket and the bottom bracket are each made from a corrugated plastic material.
 18. A method of reinforcing a floatation device comprising the steps of: a) providing an assembled floatation device having an outer resin coating, a top surface and a bottom surface; an elongated top bracket comprising a top side, a bottom side, and a peripheral side edge; an elongated bottom bracket comprising a top side, a bottom side, and a peripheral side edge; and a fastening means that fastens each bracket to the outer resin coating of the floatation device; b) fixing the top bracket to the resin coating of the top surface of the floatation device with the fastening means and fixing the bottom bracket to the resin coating of the bottom surface of the floatation device with the fastening means.
 19. The method of claim 18 wherein the fastening means is a strip of adhesive covered by a protective liner, and the following step is inserted between steps a) and b): a′) removing the protective liner from the strip of the adhesive of each bracket. 